This invention relates to a brush module assembly wherein a plurality of modules with brushes therein are cooperative with slip rings on an aircraft to conduct electricity to deicers on propeller blades and more particularly to a brush module assembly having replacable modules wherein the brush modules are capable of being stacked to provide as many brushes as are necessary to mate with the corresponding slip rings. Heretofore, in the use of brushes with slip rings, a brush holder was molded out of plastic into a two piece unit, which pieces had intricate parts to hold the movable brushes, springs, guide rods and the electrical connections. The fabrication of the molds are extremely expensive and their use was limited to the precise slip ring for which they were made, since the clearance space varied with engine propeller and air frame construction as well as slip ring diameters and configurations. The present invention contemplates a module type of construction which was versatile in its adaptation to the number of slip ring, their location and the clearance space available between the engine, propeller, or all frame members. In addition, the modules could be spaced from each other by a spacer means to modify the spacing arrangement to facilitate its use with a slip ring arrangement whose radial distances varied. The size of the spacer means in cooperation with the modules permits greater flexibility of use, increased standardization of parts with its corresponding reduction in overall inventory and greater economy in production since the intricacy of mold and its parts is reduced significantly thereby permitting the use of less costly tooling. A further advantage of the module assembly is that it is easier to replace worn brushes in the field since the brushes do not have to be desoldered from connectors. This eliminates problems caused by cold solder joints and shorting shunt leadwires.